1. Field of the Invention
The present invention relates generally to image reproduction machinery, and more particularly relates to envelope feed apparatus for printers, copiers and the like.
2. Description of Related Art
Modern image reproduction machines, such as printers and copiers, are typically provided with one or more paper supply trays, each of which is removably insertable into an associated opening formed in the outer housing of the machine. Each tray is adapted to hold a stack of cut paper sheets--typically of 81/2".times.11" or 81/2".times.14" size--for infeed to the internal printing portion of the machine and subsequent discharge from the machine housing into an external paper receiving structure.
The handling of envelopes is conventionally accomplished utilizing a separate feed structure externally built onto the housing, normally on a side thereof opposite from the paper supply tray or trays. These envelope feed structures are adapted to hold a single stack of envelopes and successively deliver the envelopes into the interior of the housing for feed therethrough via a path different than that of the paper entering the housing from the opposite side.
Compared to a single sheet of paper, an envelope is quite thick, having four or five stacked layers of paper at the point where its flap overlaps the central back side of the envelope. Accordingly, far fewer envelopes than cut paper sheets can be placed in a stack of a given height. This large stack height associated with envelopes has heretofore limited the number of envelopes that could be held at one time in their dedicated single stack exterior storage structure. Accordingly, when large numbers of envelopes are to be imprinted in a given run, it is necessary to frequently re-load the exterior envelope storage structure with a new single stack of envelopes to be fed into the machine.
It can be readily seen from the foregoing that it would be desirable to provide image reproduction machinery, such as printers and copiers, with improved apparatus for storing and infeeding envelopes. It is accordingly an object of the present invention to provide such improved apparatus.